Internal-combustion engine.



R. D. STEVENS.

:NTERNAL coMusTloN ENGINE.

APPLICA-HON HLED OCT. 28| 1912- -1 ,137,296. Patented Apr. 27, 1915.

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INTERNAL COMBUSTION ENGINE.

APPLICATION FILED 00128. I9I2.

i foreign matter U] TES PATENT OFFICE,

" nay D. STEVENS, or sAN BEnNARDINo, CALIFORNIA.

, INrnnNAL-coMBUs'rIoN ENGINE.

To allee/omit may concern:

Beit known that -I, RAI citizen of the United States, .residing at SanBernardino, in the county of San Ber- 5 nardno and.' State ofCalifornia,vhave in vented V.new and useful Improvements in,Interni-'Qnbilstion Engines,"'of which the followin' 'g2 alspecication.v "ventionv latesto internal comengiiesfof .the four-cycle type inwhichffaeombustible mixture ,formed outside the engine' is introducedinto thercylin- Vder' durin he suction stroke of the piston and inf wreturn of the pistons:

My invention relates particularly to the devices that control theadmission of the fresh gases and the escape of burned gases.

` In engines of this type, as heretofore con.

structed, lift' or puppet valves operated either by the pressure of thegases or of the atmosphere, -or by suitable cam mechanism have generallybeen employed and experi! ence shows that the use of such valves is'open to many objections.

, The' general object of m 1'invention is to provide for admission anexhaust vof the gases by means which shall obviate the obso )actionsabove 'referred to, and this result is attainedby using reciprocatingpiston valves 'having'j'in 4911 their ends. 'These rings preventjl ge ofgases, assist in the lubrication, "and wip: out Vcai-ben and otheroxmthe valveseat and so prevent it fromffnseatingjthe valve. The ringsalsopause tire-valve chamber to wear even,'. and expand as the chamberbecomes worn," jtl iusfpreventing leakage. 40.

One 'specific object of my invention is to secure*- self-lubrication of.the valves,l the same being surrounded with. awater-jacketed'yalvechamber in which said valves operate easily andlcoolly.

is -to securev the automatic removal of. dirt, cai-bon and grease fromthe valve seat and to convey the same to some exterior point where thesame may'be conveniently disv5t.) charged.

Another specific object of ray-invention is to securea considerablereduction in.' the gasfrictionfas the mixture passes'through the valveports, the same permitting a freer Specicati'on of Letters Patent.

D. STEVENS, aV

ch the burnt gases are driven l5 from the cylinders after.v combustionby the vshows the square bushin Another, specific object of my inventionrush of said mixture into' and exhaust strokes.- This feature operatesto increase the useful power of my engine by reducing lost work ofadmission and exhaust, and obviously secures the admin-- ytage. of anincreased over all engine ei- V ciency.

' Another specific object of' my'inventionfis to secure va. positivereturn ofthe valves,v

' is that I secure rapid valve motion during.

the haflf cyclein which the valves are active and secure a valve dwellor rest during the hal-f cyclein which the valves are inactive. Thisfeature permits the-use of a comparatively short valve and valve seatand reduces wear on the same.v

lhe accompanying drawings illustrate the invention.

Figures 1, 2" and 3 are diagrammatic views in axial section through anlengine embodying my invention,and showing the position of the valveoperating gear at critical points of the cycle. 'Fig 4 isl an enlargedplan section'of .the engine taken on line ic,

Fig. 5, the dust guards surrounding the valve casings being omitted 'inthe interest of clearness. 'Fig. 5 is a vertical'axial secand out of thecombustion chamber during the admission Patented Apr, 27,1915.

application ined octqber ae, 1912. sei-iai No. 728,273.

tion through the engine showing the details i and relative positionofthe valve operating gear, piston and the c linder. Section is taken online w, and 6. Fig. G is a sectional'elevation along line ai of Figs. 4and 5, showing myv improved valves.v Fig. 7 is a plan section on line:v-?, Fig. 5, and and square rod for carrying the roller fo lower..

1 is an ordinary four cycle gas engine cylinder provided with 3, andspark plug 4.

piston 2, Vwater jacket At diagonally opposite points',and built iintegral with the cylinder,l are the valve chambers 5 and 6, having thetransverse inlet port 7 and exhaust port 8 respectively. Through' thesevalve chambers pass the cylindrical apertures 9 and 10- serving as seats'for valves as later described, the said apertures or seats being closedat their upper ends by; walls 11 and 12. Through'tliese walls pass oilports 13 and 14, connected with a suitable oilvsupply not shown and.v

also breathingapei'tures 15 and 1("perinit ting the admission anddischarge of air from the upper portion ofthe chambers during normaloperation of the valves 17 and 18.

Each 'of the valve chambers is provided with a novel cylindrical pistonv a'lve as shown at 17 and 18, similarly constructed,"

and having the packing rings 19 and 20. to form a gastight joint betweenthe valve and its seat. These ringsare resilient and will automaticallyadjust themselves to take up lany wear of the cylindrical seats J and1Q.

- Valves 17 and 18 are each provided with a funnel shaped inwardlylexpanding' port 21 bounded above by the upwardly and inwai'dly extendingwall :22, on'tlie side by the inwardly diverging walls 23,' and on thebottomby the horizontal wall 24. As the lcontrollingedge 25 of port 21is raised, un-

covering the lower outer edge 26 of port '7,

an expanded passagel through tlie'valve is pnovided, permitting gas torush freely into the cylinder. Due to the expanded shape of said valveport the gas will be subject to 'l minimumiriction or resistance duringits sion stroke thisreduct-ion of gas friction re` passage through thesaine. On the adinisduces the back pressure on the piston face andthereby the lost or pumping work-of ad' mission. Durin the l`exhauststroke the similar easier exit lol" burntgases through The lubricatingoil, entering vthe valve' chambers by'p'orts 13 and 14, fills thereservoirs 27, and as the valve oscillates during operation, theoil isthrown out covering the upperx'portion of the valve seat. The oil willflow down along the seat to the rings 19 and 20 making a more perfectseal between the ringsand seat, and also reducing Vthe sliding frictionbetween the saine. Un-

-. dervlthe influence A,of theexploded or comy Through this notch anadditional aniountol lubricant over and above the normal qua-npressedgases the valves are pressed most forcibly against the outer portion ofthe va'lve seatl tending to cause the'greatest friction and wear there,and in order to supply a proportionately Vgreater amount'of lubricant.to this side, notch 28is cut vinto the upper edge of reservoir 27 atits outer point.

5 ti'ty-provided by the splash system will feed to the outer surface ofthe valve and coun.-

teract the increased wearing tendency. The

"valve chainbersgare also built tion in Fig. 5.

"3l and 232 oll the ports with. a 'Water jacket :29 surrounding both thevertical valve seat and the horizontal ports 7 and 8. Bv

this provision the valve is kept cool and its lubrication more readilyeffected. and at the saine time the gases passing through the ports arekept cool and therefore condensed.,

.securing the. passage ofniaxinium weight of gas with ininnniiniexpenditure ot power.

A downwardly and outwardly inclined -dirt groove 3U is cut into valves17 and 18,

the former being shown in its-lowest posil-`roni this figure it is seenthat the inner extremity of the dirt groove is never uncovered to the cvlinder side ot' ports 7 or S, but that the lower outer ex treniity ofthe groove is vopened to the outer side of ports 7 oi' b' when the valvehas reached thc-lowest point in its travel. .The

edges of this groove will scrape the dirt, cai-bon and other foreignmatter oiithe valve seat into the groove, such dirt passing down theinclined groove falling onto the ledges 7 and S respectively. Ifpermitted to remain on ledge 31 of the inlet po1t,the inrusliiiig gaseswould draw the 'grit into the engine cylinder where damage might be doneby cutting the cylinder i-ore. The ledge 31 is therefore inclined andthe grit will run down and olf the saine into tlieadjaccnt receptacle 33provided in the inlet pipe 3-1. The receptacle 33 is provided with adetachable portion 35 from which the grit may be discharged at suitableintervals. No such provision need-be iii-ade at the exhaust ledge 32 thegrit being carried away from the engine by the exhaust gases issuingthrough the valve port.

Each of the valves are connected through pins 36 to the rods37 carryingat their lower; ends'the cain follower 3S operating iii con-v j iinctionwith positive return cains described below, to move the valves in'correct time relation. with respect to the position of the powerpiston2. ,f v

, The piston :2 carries the connecting rod 39, coperating with-crank l0and power shaft 41 in the usual manner. The gear lil on the' powershaft, meshes witlipinions 43, carried by the lay shafts 44. Thepinions43 are of the same diameter, and double that of gear 12, this'ratiocausing cach pinion to'` make one revolution during four strokes or onecycle of the engine, the gear having inade two revolutions'in the sametime. Mounted on the lay shafts 44 and revolving withv the pinions arethe rapidly acting positive return cams 45 seen best in Fig. 6,- tlieserains being formed withfthe grooves 46 in which run the followers 38imparting thev cani motion to valves 17 and 18.

In Fig. 5,v the piston is shown at its mid poii 1 t during the exhauststroke, and it is s efen that the-follower 38 of the admission valve isat the end of a dwell or rest period determined by the dwell lobeextending from point 4i' to point 4S on the semi-circular portion l5)ot' the cam groovev and lasting from` the iiiiilcoiiipression totheinidexhaust points of the cycle. During this dwell there has been nofunction for the admission valve to perform and it has been allowed torest motionless,causing no un-- necessaiv wear either upon the valve -orits the follower lies under line ac, shown best in Fig. 5. proximately45 to the major cam diameter (al. T he exhaust fcam and valve operate ina manner identical with that of the inlet mechanism. except in po'int oftime, the eX- l'iaust cam leading the inlet cam by 90 on the lay shafts.By use .of my valve operating. gear thc life of the valves is prolonged,

all unnecessary wear being avoided, and during the operating portion ofits stroke thc inotiiin ot; -the valve is accomplished with despatch.securing an 'effective opening of both .ports for the admission andexhaust "of the gases. From the foregoing it is seen that thecylindrical valve chambers 9, 10 eut through the'ports 7, 8 so as todivide said ports into axially al'ined inner and4 outer bores that arerectangular in cross section and that vthe cylindrical valves 17, 18reciprocating in said valve chambers are provided with transverse ports.therethrough and that each of said valve ports has an oblique upperwall designed to extend downward and outward between said bores from theupper side of the inner bore to the lower side of the outer bore whenlthe valve is closed. .This construction .is of advantage to securemaximum thrust of the compressed gases in the cylinder against the valveso as to produce maximum tightness of the valve against leakage and,furthermore, is very important for reducing impediment of the fiow ofgases to and from the cylinder since the valve ports 21, 22 are alwaysfully openedl to the inner bores of the ports 7, 8 even when the. valvesare closed,'so that in reality the onlyr obstruction to the flow ofgases is the outer walls 'of .the valves. v

In Figs. 5 and 6 are sliown dust guards. or protecting hoods 50,suitably attached to the cylinder by means of studs 51 and wing nuts 52,the guards surrounding the valves and operating rods to prevent dustfrom ac-` cumulating and interfering with -the op'erathe lower valveportions for repair or adtion of the same. To expose the rods 37 and Thelines ab and ac are located ap.

justment, the guards 50 may be-rapidlyre- Q moved byv merely unscrewing.the wing nuts 52. l

The engine -works according'to the wellknown four cycle principle, andfrom the foregoing itisA thought the operation of the elements embodyingmy invention. will be readily understood.

1. The combination with an engine cylinder having a, port, .of acylindrical valve chamber cutting through the port and dividing saidAport into inner and puter bores,

and a cylindrical valve reciprocating in said valve chamber and providedwith a transverse port therethrough, said valve port having an obliqueupper wall designed to extendl downward and outward between said A bores'from the upper side of the inner bore to'the lower side ofthe outerbore when the valve isclo'sed. l

2. Inlet valve mechanism for gas engines, said mechanism comprising acylindrical valve chamber, a cylindrical piston valve adapted to operatein said chamber, said valv chamber having one port communicating ith theengine and another port leading into saidvalve chamber, the lowerportion of the last said port being inclined downwardly, outwardl andaway from said valve chamber, the cy indrical face of said piston valvehaving a downwardly and outwardly extending dirt groove cut therein,said dirt groove .-being adapted to open into the last said port and todeliverdirt thereto` and a removable receptacle mounted adjacent thelower portion of the last said port, said receptacle being adapted tocollect the dirt deposited by vsaid dirt oove.

33. A valve mechanism Aor gas engines comprising a cylindrical member toform a valveV chamber, a cylindrical piston valve adapted to operate insaid cylindrical member, a. port communicating with the engine being'formed in one side of said cylindrical member; and a second portbeing'formed in the other side of the cylindricalxmeinber, there being atransverse port in said piston valve adapted to register with the portsthrough the cylindrical member, and a groove cut lin the cylindricalface of said piston; said groove extending downwardly and outwardly.andbeing adapted to-open into said second port and to deliver c abon' ber,an inlet pipe secured to said cover and affording communication intosaid valve chamber, a cylindrical'piston valve adapted to 'operate'insaid chamber, said piston valve ino -valve chamber, a cover for saidvalve cham i being formed with an` upwardly open` g i cup-shaped portionadapted to form a Vredgvoir for lubricating oil which may be suppliedthereto through said inlet pipe,'ss 1d,

YVthrough that partl Aof its side. which vis re nfl'oved from. thepiston cylinder, said aper`l Vinle'fbeirlg adapted to feed lubricating'ol l5 :.frbmsalid up-shaped reservoir n the valve to the walls ofthegva1 vechamber which are removed from the enginel cylinder.

In testl-of"Whereof I have hereunto st` 11.1l piesenvce o-f-,g

OLGAv S. CASEY, WM. MANsoN.

RAY D. STEVENS.

